Database systems, including Relational Database Management Systems (“RDBMS”) are sometimes required to accommodate geospatial data types that can store such spatial features as points, linestrings, polygons, multipoints, multilinestrings, multipolygons, and geometry collections. Such spatial features can be used to represent a wide variety of useful information, such as geographical elements on maps, network elements on a chart of a company's communications network, or elements on a company's organizational chart. Some of these spatial features, such as a polygon, which is planar area bounded by a closed path or circuit composed of a finite sequence of straight line segments meeting at vertices, and a multipolygon, which is a set of two or more polygons, can contain a large number of vertices and they can contain one or more interior rings, which are open areas bounded by a closed path or circuit.
Representing a spatial feature containing one or more interior rings within a database is a challenge.